RFR: Slightly simpler way of waiting for a specific time [v2]

[kabutz]

> Instead of writing the logic for calling System.nanoTime() etc. ourselves, could we perhaps use awaitNanos() instead?

kabutz has updated the pull request with a new target base due to a merge or a rebase. The incremental webrev excludes
the unrelated changes brought in by the merge/rebase.

-------------

Changes:
  - all: https://git.openjdk.java.net/loom/pull/19/files
  - new: https://git.openjdk.java.net/loom/pull/19/files/c4a2bd29..c4a2bd29

Webrevs:
 - full: https://webrevs.openjdk.java.net/?repo=loom&pr=19&range=01
 - incr: https://webrevs.openjdk.java.net/?repo=loom&pr=19&range=00-01

  Stats: 0 lines in 0 files changed: 0 ins; 0 del; 0 mod
  Patch: https://git.openjdk.java.net/loom/pull/19.diff
  Fetch: git fetch https://git.openjdk.java.net/loom pull/19/head:pull/19

PR: https://git.openjdk.java.net/loom/pull/19